Apparatus for fabricating a bearing device

ABSTRACT

An apparatus for fabricating a bearing device comprising a housing having an opening therethrough, a ball-shaped swivel member positioned within the opening and spaced from the surface of the housing which defines the opening, and a raceway of solidified bearing material in the space between the swivel member and housing, the raceway having a swiveling clearance with and retaining said swivel member in the housing, the inner surface of the raceway being shaped to correspond to a part of an elongated sphere. In the fabrication of this bearing device, the swivel member is reciprocated relative to the housing during the hardening of liquefied bearing material injected into the space between the swivel member and housing. The apparatus which accomplishes this method includes relatively movable members which engage, respectively, the housing and the swivel member, these mold members providing the relative reciprocatory movement.

[451 May 22,1973

leed Sas Pawn@ m91 Davies et al.

PATENTEL MY 2 2 |975 SHEET 1 UF 3 FIGJ Flel

PTENTED HY 2 21975 SHEET 2 nf 3 PATENIEnmm SHEET 3 UF 3 APPARATUS FORFABRICATING A BEARING DEVICE This is a Divisional Application ofApplication Ser. No. 1,733 filed Jan. 9, 1970, now U.S. Pat. No.3,629,921.

BACKGROUND OF THE INVENTION l. Field of the Invention This inventionrelates generally to a bearing assembly which includes a ball-shapedswivel member retained for swiveling movement in a housing by means of araceway of bearing material, and more particularly, to such a bearingassembly in which the raceway in its fabricated form has a positiveswiveling clearance with the swivel member, to a method in which thehousing and swivel member are reciprocable relative to each other inorder to produce the positive clearance between the swivel member andthe raceway, and to anA apparatus used in molding of the raceway wherebythe swivel member and housing are moved relative to each other duringhardening of liquefied bearing material injected into the space providedfor the raceway.

2. Description of the Prior Art In the manufacture of such a bearingassembly, it is necessary that the swivel member be freely swivelableuniversally within the housing with a minimum degree of looseness. It isalso desirable that the raceway-of bearing material separating theswivel member from the housing be secured to the latter againstmovement.

ln the past, certain plastic bearing materials such as polyamides andpolycarbonates have been used in the formation of the raceway, but thefinished bearing assembly has not been altogether satisfactory becauseof excessive tightness of the swivel member in the raceway andloosenssof the raceway in the housing. One method employed for moldingthe raceway has been to use a thermoplastic or thermosettingplastic'material injected into intimate engagement with the swivelmember and hardened in this intimately engaged condition through the useof strictly controlled, relatively low pressures which tend to precludeshrinkage of the plastic onto the swivel member which otherwise wouldlock the swivel member against movement. This technique has not beensatisfactory as it imposes stringent process controls which result inhigher costs because of the inability of the process to produce closepiece-topiece uniformity.

SUMMARY OF THE INVENTION In accordance with the broader aspects of thisinvention, there is provided a method of fabricating a bear'- ingassembly comprising a housing and a ball-shaped swivel member, in whichthe swivel member is positioned within an opening in the housing so asto provide a space surrounding the swivel member. The liquefiedhardenable bearing material is then injected into the space and becomesengaged with both the housing and the swivel member. The swivel memberand housing are continuously moved relative to each other in a directionthat alters the shape of the space until the liquetied bearing materialhardens. The characteristic of this continuous relative movement is suchthat it results in free omnidirectional movement of the swivel memberwithout excessive play.

More specifically, the swivel member is reciprocated relative to thehousing in a direction parallel to the axis of the opening whereby theraceway will have the diameter of the swivel member taken in a planenormal to the axis but as to its dimension at right angles thereto, itwill be slightly longer than the swivel member thereby providing forproper swiveling clearance.

The apparatus includes a first mold means at least partially closing theopposite ends of the annular space between the swivel member and thehousing, second means for holding the swivel member in position in saidhousing and for completing the closure of these opposite ends, the firstand second means being relatively movable whereby said swivel member maybe reciprocated relative to the housing, and means for filling the spacewith liquefied hardenable bearing material which hardens during therelative continuous movement between the swivel member and the housing.

It is an object of this invention to provide an apparatus for molding araceway of bearing material in such a bearing assembly in a manner thatprovides an operating clearance for the swivel member without additionaloperations being required after molding.

A further object of this invention is to provide an apparatus formolding a raceway into such a bearing assembly wherein the housing andthe swivel member are continuously moved relative to each other duringthe injection phase of the molding cycle.

The above-mentioned and other features and objects of this invention andthe manner of attaining them will become more apparent and the inventionitself will be best understood by reference to the following descriptionof an embodiment of the invention taken in conjunction with theaccompanying drawings, wherein:

IN THE DRAWINGS FIG. l is a side elevation of the housing part of oneembodiment of this invention;

FIG. 2 is a fragmentary axial section thereof;

F IG. 3 is a side view of the completed assembly partially sectioned forclarity of illustration;

FIG. 4-is an axial sectional view of the embodiment of FIG. 3;

FIG. 5 is a side view, partially sectioned along the section line 5 5 ofFIG. 7, of an apparatus used in fabricating the bearing assembly of thisinvention;

FIG. 6 is an enlargement in cross-section of a part of the arrangementof FIG. 5;

FIG. 7 is a top plan view of the lower mold section of the apparatus ofFIG. 5 with two bearing housings positioned therein;

FIG. 8 is a cross-section of lower mold plate of FIG. 7 takensubstantially along section line 8-8 thereof; and

FIG. 9 is a side view in longitudinal section of motion-producingapparatus whereby the apparatus of F IG` 5 is operated.

DESCRIPTION OF EMBODIMENTS within an opening 18 in the head l2. As shownmore`- clearly in FIG. 2, the opening 18 may be part spherical asindicated by the numeral 19 generally conforming to the curvature of theball 16 and is provided midway between the surfaces 24 with an annularcoaxial recess 20. The end portions of the opening 18 at 22 whichextends from the part spherical curvatures 19 outwardly to the surfaces24 are cylindrically shaped and of equal diameter. The two surfaces 24are flat and parallel, lying in planes normal to the axis 26 of theopening 18. The parts 19, 20 and 22 of the opening 18 are coaxial aboutthe axis 26.

The ball 16 in this rod end is of conventional design having a coaxialbore 28 adapted to receive a mounting stud or the like (not shown) andfurthermore has flat parallel surfaces defining opposite sides 30 which,when the ball 16 is centered in the head 12 as shown in FIG. 4, lie inparallel planes positioned outwardly from and parallel to the headsurfaces 24 as shown.

The ball 16 in the design shown conforms generally to the curvature 19of the opening 18 (FIG. 2) but is of smaller diameter so as to provide aring-like clearance or space therebetween defined at the outer peripheryby the parts 19, 20 and 22. This space is occupied by a raceway 32(FIGS. 3-4) of bearing material secured in the head 12 by means of theannular groove 20 and two trunnion-like appendages 35 which fill diametrically opposite openings 33 in the head 12 as shown in FIG. 3. Withthe raceway 32 properly formed, the ball 16 will swivel freely and besecurely mounted in the housing 10.

Referring more particularly to FIGS. through 9, the apparatus utilizedin making the bearing assembly of FIGS. 3 and 4 will be described. Ingeneral, the apparatus performs the operation of molding the raceway 32in such a manner that proper operating clearance for free swivelingmovement of ball 16 is provided without any additional operations beingrequired after molding. The molding apparatus generally comprises twomold sections, an upper section 34 and a lower section 36. The lowersection 36 may be considered as stationary and the upper section 34 asmovable vertically for opening and closing the mold. Specifically, theupper mold section 34 is adapted to be mounted in a conventionalinjection molding machine by being attached to the movable platen of themachine whereby it can be raised and lowered relative to the stationarymold section 36, which is attached to the stationary platen. These moldsections 34 and 36 having parting surfaces 38 and 40, respectively, andwhen closed, define a cavity 42 corresponding to the shape of thehousing 10 as shown in FIG. 1, a part of the cavity indicated by thenumeral 44 (see FIGS. 5 and 6) being formed in the upper section 34 andan opposite part 46 being provided in the lower section 36. In theenlargement of FIG. 6, it will be apparent that cavity portion 46 islarger than portion 44. While the cavity portion 46 conforms to theexternal contour of the housing 10, short cylindrical wall sections 48are formed with some clearance with respect to the housing so as topermit the latter being inserted into and removed from the cavityportion 46. f

The lower mold section 36 is rigidly mounted on the stationary lowerplaten of the machine. An ejector plate assembly 50 is verticallymovable relative to mold section 36, being guided with respect theretoby return springs 52 and pins 56, there being four such pins and springassemblies located near the comers of the assembly which issubstantially rectangular as shown in FIG. 7. The spring 52 iscompressed between the upper surface of the plate 50 and the base of asocket 54 in the mold section 36 whereby the latter is yieldably urgedupwardly relative to the plate 50. To serve as a guide, the pin 56having a head 58 locked into the plate assembly 50 extends upwardlythrough the spring 52 and is slidably received in a bore 60, as shown.

There are two mold cavities provided in the apparatus, these beingindicated by the numeral 42 in FIG. 7. A sprue passage 62 of T-shape isformed into the two parting surfaces 38 and 40 and is provided withtunnel gates 64 which connect with cavity portion 46 as shown moreclearly in FIG. 6. Exhaust runners 66 are also provided in the partingsurfaces 38 and 40 and extend from the side of said cavity portion 46diametrically opposite from the gate 64 and opens to atmosphere.

Mounted on the ejector plate assembly 50 and extending upwardlytherefrom is a runner ejector pin 68 slidably received by a passage 70in the mold section 36.

Both of the mold sections 34 and 36 are provided with vertically alignedcylindrical bores 72 and 74, respectively, which are of equal diameter.Two cylindrical mold inserts 76 and 78 are received, respectively, bythe bores 72 and 74 for reciprocation therein. The insert 76 has a head79 of enlarged diameter, this head being reciprocably received by asocket 80 of complementary shape in the mold section 34. Similarly, theinsert 78 has an enlarged diameter head 8l which is reciprocablyreceived by a cylindrical socket 82 for vertical guiding movement in thelower mold section 36. This enlarged head 81 is spaced above acylindrical supporting pedestal 83 on plate assembly 50 by means of acompression spring 84. The pedestal 83 coaxially receives for reciprocalsliding movement a headed pin 86, as shown, which is threaded coaxiallyto the insert 78, as shown. The upper end of the pedestal 83 is providedwith an upstanding tubular portion 88 received in a companion socket 90in the enlarged head 81 to guide the latter and the insert 78 for trulyvertical movement relative to both the pedestal and the lower moldsection 36. The guide pin 86 obviously moves with the insert 78.

The facing surfaces of the two inserts 76 and 78, as best shown in FIG.6, are spherically concave at 92 and 94, respectively, to conformprecisely to the curved exterior of the ball 16, as shown. Both inserts76 and 78 are also provided with vertically aligned coaxial bores 96 and98 of substantially equal diameter which receive therein when closed theopposite ends, respectively, of a guide pin 100. This guide pin 100 ispress-fitted and thereby secured to the insert 78 and is slidably fittedto the insert 76 by reason of a slight clearance with the bore 96.

As is shown more clearly in FIG. 5, the heads 79 of the two inserts 76protrude above the mold section 34. It should also be noted that thereis a clearance between each head 79 and the bottom of its socket 80.

Loading of the apparatus preparatory to a molding operation will now beexplained. First, the injection molding machine in which the apparatusis mounted is operated to lift the upper mold section 34 several inchesabove the upper surface 40 of the lower section 36, the inserts 76 beingcarried upwardly therewith leaving exposed the upstanding guide pin 100centered in the lower cavity portion 46 (see FIG. 6).

Two housings are placed in the cavity portions 46 as shown more clearlyin FIGS. 6 and 7. Two gate passages 33 on opposite sides of the head 12are positioned to communicate with the gate 64 and the exhaust runners66. A ball 16 is fitted over the guide pin 100 to nest in the socket 94which fits precisely the curved contour of the ball 16 as shown.

The upper mold section 34 is lowered into operative engagement with thelower section 36 whereby the concave surface 92 of the insert 76 willprecisely sealingly engage the ball 16 exterior and the upper end of thepin 100 will enter the guide bore 96. Considering FIGS. 5 and 6,application of downward force to the head 79 will result in applicationof this same force to the ball 16 and the insert 78. By using anadequate force, the insert 76, ball 16 and insert 78 may be moveddownwardly in unison against the upward force of the spring 84. Byrelaxing this downward force, the spring 84 will move the insert withthe ball 16 clamped therebetween upwardly. By controlling the downwardforce applied to the insert 76 and selecting a proper spring 84, the twoinserts 76 and 78 with the ball 16 clamped therebetween can be made toreciprocate vertically uniformly over a predetermined distance.

Plastic bearing material injected into the sprue 62, under normal highinjection pressures, typically from 10,000 to 25,000 pounds per squareinch, flows through the gate 64, the respective passage 33 and into theannular space between the ball 16 and the inner surface of the opening18. Once the annular space, denoted rby the numeral 102, is completelyfilled with plastic, the excess will flow out of the opposite passage 33and the exhaust runners 66. After the bearing material hardens, theupper mold section 34 is lifted from the lower section 36 and thebearing assembly of the ball 16 and the housing 10 is removed from theapparatus. The ball 16 is retained in the housing l0 by means of theplastic liner or raceway 32 that fills the space 102.

As viewed in FIGS. 5 and 6, the cavity portions 44 and 46 have opposedsurfaces which conform to and sealingly engage the opposite surfaces 24,respectively, of the housing 10, as shown. Each of these cavity portions44 and 46 have internal diameters defined by the bores 72 and 74,respectively, which are substantially smaller than the maximum diameterof the opening 18 and slightly smaller than the diameter of the ball 16.Ideally, the perimeters of the sealingly engaged surfaces 92 and 94,respectively, should be in the form of a knife-edge; however, in orderto maximize wearlife of the apparatus, a small flat annular surface oredge 104 joins the periphery of the surfaces 92 and 94 with theperiphery of the inserts 76 and 78. The radial flat of this small edge104 needs to be no more than 0.005 of an inch. As shown in FIG. 6, eachedge 104 lies in a flat plane coestensive with the plane of therespective surface 24, when the apparatus is closed.

With the mold apparatus closed, as shown in FIGS. 5 and 6, and thehousing l0 and ball 16 in place, the cavity 102 will be bounded on oneside by the surface of the ball 16 and on the outside by the innerhousing surface 18. The opposite ends of the cavity 102 will be definedby the respective flat surfaces of the cavity portions 44 and 46 as wellas the edges 104 of the two inserts 76 and 78. These inserts sealinglyengage at the surfaces 92 and 94 the ball 16 so as to prevent leakage ofliquefied bearing material injected into the cavity 102. The cavity 102is thereby defined as being annular and having opposite ends closed bythe opposed walls of the cavity portions 44, 46, respectively.

The size relationship between the diameters of the bores 72, 74, theball 16 and the opening 18 are so related that the ends of the annularspace 102 are closed more by the cavity portions 44 and 46 than by theinserts 76 and 78. This is an important feature in obtaining thebeneficial results of this invention as explained later.

In theory, considering for the moment that the cavity 102 (FIG. 6) isfilled with liquid plastic such as polyamide, polycarbonate, urethane,polyethylene, or a suitable liquefiable metallic bearing material,vertical reciprocation of the ball 16 in the embrace of the two moldinserts 76 and 78 is not attended with similar movement of the liquefiedbearing material. One of the objectives of the diametral relationship ofthe various parts, as explained, is to confine the liquefied bearingmaterial in position in the cavity 102 thereby to permit movement of theball 16 relative thereto. This results in the ball 16 enlarging thebearing cavity contiguous with the ball surface as the liquefied bearingmaterial then hardens. The result is that the hardened bearing materialintimately engages and is thereby secured to the surface of the opening18 and an inner bearing surface of the raceway is formed which conformssubstantially to the shape of the ball 16 surface with the exceptionthat the midportion thereof tends to be of cylindrical shape therebyresulting in the inner surface resembling a sphere that has beenmicroscopically elongated, thereby providing a desired clearance withthe ball. This may be explained further by considering the ball 16 inFIG. 6 to be reciprocated over an excursion of about 0.030 inches duringthe period required for the bearing material to harden. Once the bearingmaterial has hardened and the reciprocation terminated, theball-engaging surface of the bearing material will be slightly elongatedbut will have an inner diameter in a plane midway between the twosurfaces 24 normal to the axis of the opening 18 substantiallycoextensive with the outer diameter of the ball 16.

It is important that the cavity 102 which forms the raceway 32 be ofsufficient volume and radial depth. If the volume and depth are toosmall, the raceway 32 in the nished product tends to be too tight on theball 16. By making it adequately large, in accordance with the specificexample given hereinafter, the ball 16 can be reciprocated relative tothe mass of plastic in order to achieve the swiveling clearance desired.Thus, the presence, the size and the shape of the groove or recess 20are important design aspects of this invention.

In the finished rod end, the raceway 32 is prevented from being rotatedor otherwise accidentally removed from the housing l0 by virtue of theannular rib formed by the groove 20 (FIG. 2) and also the trunnion-likeshafts 35 formed by the filling of passage 33 with bearing material(FIG. 3).

When the molding operation is completed, lifting of the mold section 34off the lower section 36 results in some upward movement of the moldinsert 78 underl the influence of the spring 84. This severs the gate atthe surface of the housing 10 thereby leaving the trunnions 35 asintegrated parts of the rod end. Elevation of the ejector plate assembly50 lifts pins 56 thereby unseating the sprues.

In the molding of the raceway 32, it is important that the cavity 102(FIG. 6) completely fill. This is assured by providing the exhaustrunner 66 such that a slight amount of overflow insures filling of thecavity 102.

In FIG. 9 is illustrated the mold apparatus just described incombination with an actuating mechanism for reciprocating the inserts78. This mechanism includes a simple lever 106 pivoted at 108 to amember fixed with respect to the mold section 34 having portions onopposite sides of the pivot 108 engageable at 110 and 112 with the twoinserts 78, respectively. The outer end 110 of the lever 106 is providedwith furcations 111 and 113 which engageably straddle eccentricallymounted wheel 112 which rotates about a center l 14. As the eccentric112 rotates, the lever 110 will be reciprocated vertically therebycausing a corresponding movement of the portions 110 and 112 ofthelever. As one mold insert is being forced downwardly, the other onerises under the force of the respective springs 84.

With a diameter of about 0.740 inches for the recess in the head 12, adiameter of 0.630 inches for the parts 22, a ball diameter of 0.625inches, a dimension of eleven thirty-seconds inches between the two flatsurfaces 24, a width of 0.156 inches for recess 20, a diameter of 0.554inches for the bores 72 and 74, and a plastic bearing material of glassreinforced nylon, it has been found that a stroke of 0.030 inches at arate of 1,700 cycles per minute provides free-swiveling movement of theball 16 in the plastic raceway 32 without any undue looseness. If agreater or lesser degree of swiveling freedom is desired, the length ofthe excursion may be correspondingly altered, increasing the excursionproducing greater freedom of movement.

For the typical parameters just given, eccentric 112 is rotated at aboutl,700 rpm thereby reciprocating the inserts 78 at a corresponding rate.The plastic injected into the cavity during the operation is atrelatively high pressure, from about 10,000 to 25,000 pounds per squareinch. Reciprocatory movement of the inserts and the ball 16 is startedprior to the injection of the liquid plastic into the cavity 102 andcontinued until after the plastic is hardened.

A plastic bearing material found to be operable is glass reinforcednylon containing in parts by weight 40 parts fiber glass of about l/8inch to 1/4 inch fiber length, 100 parts nylon and 5 partsmolydisulphide. Other compositions for bearing material, both plasticand metal, may be used without departing from the basic concepts of thisinvention.

This rod end removed from the molding apparatus needs no furtheroperations in assuring proper swiveling clearance for the ball.

Upon hardening, it is theorized that the plastic has some memory andwill shrink toward the ball 16 thereby tending to assume the shape ofthe ball; By controlling the size of the reciprocatory excursion, theactual finished clearance between the ball 16 and the bearing raceway 32can be controlled.

The concepts of this invention allow production of rod-end bearingassemblies such as shown and described in which the ball 16 will neitherbe too loose nor too tight in its raceway of bearing material. It hasbeen found that the rate of vibration, the length of the vibratoryexcursion and other manufacturing Steps including the smoothness of theball 16, can be varied for obtaining desired swivel freedom in thefinished product. For example, the pressure and temperature at themoment of injection are not found to be critical. Thus, losses due toimperfectly formed assemblies are minimal thereby leading to highproduction efficiencies and corresponding lower costs.

In the finished product, the ball 16 is found to have a relatively largeswing angle and substantial strength against dislodgement from theraceway 32. The raceway 32 itself is formed of bearing material having amaximum degree of lubricity as compared with the housing that containsit. The thickness of the head 12 as viewed in FIG. 2 can be madesubstantial thereby providing a maximum amount of strength in thehousing itself. The housing need not be deformed or altered after themolding operation to assure proper retention and operating clearance forthe ball.

In summary, the vibration of the ball 16 may be started at the momentthe mold sections 34 and 36 are closed and before injection of theliquid bearing material. This vibration is continued until the bearingmaterial has solidified and just before the mold sections are opened.

While tunnel gates 64 (FIGS. 5 and 6) are disclosed, it will appear asobvious to persons skilled in the art that these may be omitted and themold cavities 44 and 46 so formed that one-half is in each of the moldsections 34 and 36. Thus, the sprue 62 would communicate directly withthe passages 33 in the housing l0. The tunnel gates 64, however, in thisinvention are preferred.

It will be obvious to persons skilled in the art that the presentinvention is not limited to rod ends, but instead relates to bearingassemblies generally wherein a swivel member such as the ball 16 ismounted for universal swiveling movement in a retaining frame orhousing. Also, it is not necessary that the housing in which the ball ismounted have a socket which opens through both sides thereof. Instead,the socket may be closed at one end, as is true for conventional balland socket assemblies, and the ball reciprocated in a straight linebetween the open and closed ends of the socket to provide the necessaryswiveling clearance after the injection of liquefied bearing material inthe clearance between the ball and socket. The ball may also be solid,that is, not be provided with an internal bore as is true of theembodiment shown in FIGS. l through 4, and furthermore can be detachablyor integrally connected to a stud of the type conventional in ball andsocket assemblies.

While FIGS. 1 through 4 disclose the trunnion-like passages 33 as beingdiametrically opposite each other, they may be located differently solong as one of them serves as an overflow to assure that the cavity 102fills completely. K

inasmuch as the housing 10 itself serves as part of the mold and themold sections 34 and 36 serve as another part, the particular shape ofthe housing 10 which partially forms the cavity can be drasticallyaltered, relying on the cavities in the mold sections 34 and 36exclusively to complete the shape of the raceway. For example, thehousing 10 as viewed in FIG. 6 could be thinner between the two faces 24thereof than shown, and even be sheet metal one-eighth inch thick, suchthat injected plastic would fill the spaces between these narrowersurfaces 24 and the cavity surfaces 44 and 46. In this instance, theplastic would essentially embrace the housing 10, or more specifically,the head 12 thereof.

Suitable cut-outs or other holding devices would have to be provided inthe mold sections 34 and 36 to embrace a peripheral portion of the sheetmetal housing and thereby position the latter in place during molding.

In one embodiment of this invention, the balls 16 are tumbled to providea smooth finish and then chromium plated. In still other instances, theballs 16 may be dipped in a suitable lubricant before the moldingoperation. Both the provision of a smooth surface and lubricant affectthe swiveling freedom of the ball in the finished product.

While there have been described above the principles of this inventionin connection with specific apparatus, it is to be clearly understoodthat this description is made only by way of example and not as alimitation to the scope of the invention.

What is claimed is:

1. For molding a raceway into a bearing assembly, said bearing assemblyincluding a supporting member provided with an opening therethrough, anda ballshaped swivel member mounted within said opening and spaced fromthe surface of said supporting member which defines said opening, saidspace being annular in shape and having opposite open ends; apparatuscomprising first mold means for at least partially closing the oppositeends of said space, second means for holding said swivel member inposition in said opening and for completing the closure of said oppositeends, said first and second means being relatively movable whereby saidswivel member may be moved relative to said supporting member, means formoving in an alternating pattern said first and second means relative toeach other in a direction generally parallel to the axis of said space,and means for filling said space with liquefied hardenable bearingmaterial.

2. The apparatus of claim 1 in which said first mold means closes alarger portion of said opposite open ends than does said second means.

3. The apparatus of claim 1 in which said first mold means includes adie having a bore portion therein, said second means includes twoclamping elements tandemly arranged and received for reciprocation bysaid bore portion, and said clamping elements having separated facingsurfaces engageable with said swivel member for holding the latter inplace.

4. The apparatus of claim 3 in which the bore portion of said die hasseparated facing mold surfaces which define a mold space therebetweenand serve as the partial closure for the opposite ends of said annularspace, said clamping elements having opposed mold surfaces,respectively, disposed adjacent to said die mold surfaces, respectively,which serve to complete the closure of said opposite ends, said die moldsurfaces closing a larger radial portion of said opposite open ends thando the mold surfaces of said clamping elements.

5. The apparatus of claim 4 including said supporting and swivelmembers, said supporting member being clamped between said die moldsurfaces and said swivel member being clamped between said clampingelements whereby said space is defined on the outer periphery by saidsupporting member, the inner periphery by said swivel member, and at theends by said die mold surfaces and the mold surfaces of said clampingelements.

6. The apparatus of claim 3 in which said first mold means closes alarger portion of said opposite open ends than does said second means,said die including two mold sections selectively movable into and out ofoperative engagement with each other, said mold sections having partingsurfaces which are sealingly engageable with each other, a cavity insaid die defined by two portions in said parting surfaces, respectively,said cavity being intersected by said bore portion and having a shapeconforming to that of said bearing assembly supporting member, saidcavity having opposite ends, one end being in one cavity portion and theother end being in the other cavity portion, the lastmentioned endsbeing defined by separated facing surfaces which extend radiallyinwardly of said opening to define circular end closures for theopposite open ends of said space, an injection sprue in said die leadingto said cavity, and an overflow sprue in said die leading away from saidcavity.

7. The apparatus of claim 6 including means yieldably urging saidclamping elements toward each other, said facing surfaces of saidclamping elements being shaped to conform to the shape of said swivelmember, and reciprocating means engaged with one of said clampingelements for alternately forcing said one element toward the otherthereby to reciprocate both in unison.

8. The apparatus of claim 7 in which said urging means includes acompression spring engaging the other of said clamping elements, and alocating pin secured to one clamping element and extending coaxiallyacross the space between said clamping elements.

9. The apparatus of claim 5 in which the surface of said swivel memberthat defines said inner periphery of said annular space is substantiallyspherical, and the surface of said supporting member that defines theouter periphery of said annular space is at least in part substantiallyspherical.

1. For molding a raceway into a bearing assembly, said bearing assemblyincluding a supporting member provided with an opening therethrough, anda ball-shaped swivel member mounted within said opening and spaced fromthe surface of said supporting member which defines said opening, saidspace being annular in shape and having opposite open ends; apparatuscomprising first mold means for at least partially closing the oppositeends of said space, second means for holding said swivel member inposition in said opening and for completing the closure of said oppositeends, said first and second means being relatively movable whereby saidswivel member may be moved relative to said supporting member, means formoving in an alternating pattern said first and second means relative toeach other in a direction generally parallel to the axis of said space,and means for filling said space with liquefied hardenable bearingmaterial.
 2. The apparatus of claim 1 in which said first mold meanscloses a larger portion of said opposite open ends than does said secondmeans.
 3. The apparatus of claim 1 in which said first mold meansincludes a die having a bore portion therein, said second means includestwo clamping elements tandemly arranged and received for reciprocationby said bore portion, and said clamping elements having separated facingsurfaces engageable with said swivel member for holding the latter inplace.
 4. The apparatus of claim 3 in which the bore portion of said diehas separated facing mold surfaces which define a mold spacetherebetween and serve as the partial closure for the opposite ends ofsaid annular space, said clamping elements having opposed mold surfaces,respectively, disposed adjacent to said die mold surfaces, respectively,which serve to complete the closure of said opposite ends, said die moldsurfaces closing a larger radial portion of said opposite open ends thando the mold surfaces of said clamping elements.
 5. The apparatus ofclaim 4 including said supporting and swivel members, said supportingmember being clamped between Said die mold surfaces and said swivelmember being clamped between said clamping elements whereby said spaceis defined on the outer periphery by said supporting member, the innerperiphery by said swivel member, and at the ends by said die moldsurfaces and the mold surfaces of said clamping elements.
 6. Theapparatus of claim 3 in which said first mold means closes a largerportion of said opposite open ends than does said second means, said dieincluding two mold sections selectively movable into and out ofoperative engagement with each other, said mold sections having partingsurfaces which are sealingly engageable with each other, a cavity insaid die defined by two portions in said parting surfaces, respectively,said cavity being intersected by said bore portion and having a shapeconforming to that of said bearing assembly supporting member, saidcavity having opposite ends, one end being in one cavity portion and theother end being in the other cavity portion, the last-mentioned endsbeing defined by separated facing surfaces which extend radiallyinwardly of said opening to define circular end closures for theopposite open ends of said space, an injection sprue in said die leadingto said cavity, and an overflow sprue in said die leading away from saidcavity.
 7. The apparatus of claim 6 including means yieldably urgingsaid clamping elements toward each other, said facing surfaces of saidclamping elements being shaped to conform to the shape of said swivelmember, and reciprocating means engaged with one of said clampingelements for alternately forcing said one element toward the otherthereby to reciprocate both in unison.
 8. The apparatus of claim 7 inwhich said urging means includes a compression spring engaging the otherof said clamping elements, and a locating pin secured to one clampingelement and extending coaxially across the space between said clampingelements.
 9. The apparatus of claim 5 in which the surface of saidswivel member that defines said inner periphery of said annular space issubstantially spherical, and the surface of said supporting member thatdefines the outer periphery of said annular space is at least in partsubstantially spherical.